When to plant Hydrangeas in Second Mesa, AZ
Second Mesa's short 167-day growing season means one Hydrangeas planting between May 9 and May 23. No fall crop in Zone 7a.
When to Plant Hydrangeas in Second Mesa, AZ
What to do in July
Your garden in Navajo County, Arizona is working on a schedule, even when you're not. Here's where you should be this July.
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Time to start hydrangeas inside
Starting these indoors now means sturdy transplants ready the moment your soil warms up.
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Pick hydrangeas
If you can't use it all right away, check the food-preservation section of your planner.
Looking ahead to August
- First harvests: hydrangeas
Hydrangeas (Hydrangea spp.) are among the most spectacular summer-blooming shrubs, with large mophead, lacecap, or panicle flower clusters lasting weeks in the garden and drying beautifully for arrangements. Native to Asia and North America alike, the genus spans several garden species with different hardiness and blooming habits. Panicle hydrangeas (H. paniculata, e.g., Limelight) are the most cold-hardy (Zone 3) and most reliable bloomers; smooth hydrangeas (H. arborescens, e.g., Annabelle) are equally tough. Bigleaf hydrangeas (H. macrophylla) are prized for blue/pink color-shifting blooms but require reliable snow cover or winter protection in Zones 5–6. Flower color in macrophylla types is determined by soil pH (acidic = blue, alkaline = pink).
Second Mesa, Arizona is in USDA Zone 7a. The average last spring frost is May 2 and the first fall frost is October 16, giving you a growing season of approximately 167 days.
At an elevation of 5,528 feet, Navajo County receives approximately 15.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 94°F, providing good warmth for Hydrangeas during the growing season. Sandy soil warms quickly in spring — great for early planting — but Hydrangeas will need more frequent watering and organic matter to retain nutrients. With low rainfall, drip irrigation is essential for growing Hydrangeas successfully. Mulch heavily to conserve soil moisture.
Second Mesa Soil Profile
Soil Type
Sandy Loam
Soil pH
7.3-8.3
Drainage
Well Drained
Hydrangeas Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Second Mesa
How your county's soil matches Hydrangeas's growing requirements.
Soil pH
Your soil pH (7.3–8.3) is more alkaline than Hydrangeas prefers (5.5–6.5). Add sulfur or peat moss to lower pH.
Soil Texture
Sandy soil in Navajo County warms quickly in spring but drains fast. Hydrangeas will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Hydrangeas.
Organic Matter
Organic matter is low (0.7%). Add 2-3 inches of compost before planting Hydrangeas.
How to Plant Hydrangeas
Hydrangeas Water Budget
Water stress score is 10/10 — consider drought-tolerant varieties and mulching
Monthly Watering Guide for Hydrangeas
Hydrangeas needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Hydrangeas Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.3" | 0" | ❄️ Dormant |
| Feb | — | 1" | 0" | ❄️ Dormant |
| Mar | — | 0.9" | 0" | ❄️ Dormant |
| Apr | — | 0.6" | 0" | ❄️ Dormant |
| May | 4.3" | 0.3" | 4" | 🚿 Regular watering |
| Jun | 4.3" | 0.6" | 3.7" | 🚿 Regular watering |
| Jul | 4.3" | 2.4" | 1.9" | 💧 Light watering |
| Aug | 4.3" | 3.5" | 0.8" | 💧 Light watering |
| Sep | 4.3" | 2" | 2.3" | 🚿 Regular watering |
| Oct | 4.3" | 1.3" | 3" | 🚿 Regular watering |
| Nov | — | 0.8" | 0" | ❄️ Dormant |
| Dec | — | 1.1" | 0" | ❄️ Dormant |
Water needs are for active growing months only (May–Oct in Navajo County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Hydrangeas Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Hydrangeas Planting Timeline — Second Mesa, AZ
Hydrangeas Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 21 | Feb 21 – Mar 7 |
| Transplant Outdoors | May 9 | May 9 – May 23 |
| Bloom | July 18 | Jul 18 – Nov 7 |
Plant 1" deep · 48" apart · Rows 60" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors |
| April | — |
| May | Transplant Outdoors |
| June | — |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | Bloom |
| December | — |
Growing Conditions
☀️ Sun
Partial Shade (3-6 hours)
💧 Water
1"/week · 2-3 times/week
📅 Days to Maturity
90–150 days
🧪 Soil pH
Needs 5.5–6.5 · Your soil: too_alkaline
🗺️ USDA Zone
Zone 7a
📆 Growing Season
167 days in Navajo County
Growing Tips for Hydrangeas in Second Mesa
Direct sow Hydrangeas outdoors after May 02 in Navajo County when soil has warmed and frost danger has passed.
Sandy soil in Navajo County dries quickly — mulch Hydrangeas with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Navajo County receives only 16" of rain annually. Hydrangeas needs consistent moisture — install drip irrigation or water deeply 2-3 times per week.
General growing tips
Plant container-grown specimens in spring or fall, spacing at least 3–5 feet apart to allow for mature shrub spread. Most hydrangeas prefer morning sun with afternoon shade, especially in Zones 7+. Keep consistently moist — the name derives from the Greek for water vessel. Prune panicle and smooth types in late winter/early spring (they bloom on new wood). Prune bigleaf types only lightly after bloom; cutting stems in fall removes next year's buds. In Zone 5–6, protect bigleaf varieties with burlap or wire cages filled with leaves over winter. Fall planting (Zones 5+) gives excellent root establishment before summer heat. Year 2+ plants reach full size and bloom.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Hydrangeas in Other Locations
When should I plant Hydrangeas in Second Mesa, AZ?
In Second Mesa, AZ, plant Hydrangeas after the last frost (around May 2) and before the first frost (around October 16). Best results when soil holds above 50°F.
What growing zone is Second Mesa, AZ for Hydrangeas?
Second Mesa sits in USDA Zone 7a. Hydrangeas grows reliably in zones 3a through 9a, so it's a good fit here.
Can Hydrangeas grow in Second Mesa's climate?
Yes — Hydrangeas grows well in Second Mesa's temperate climate. Second Mesa averages a 167-day frost-free season, with last frost around May 2 and first frost around October 16.
Your Navajo County Garden Planner — Free
A 22-page printable planner built for Navajo County (Zone 7a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.